Programming Logic
Learning Objectives
•
Understand and implement flow chart
diagrams
for
any
given
problem.
•
•
Write algorithm of any given problem.
Develop
problem
solving
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skills
What is an Algorithm?
● Algorithm is a finite set of steps which are used to
solve a problem.
● It is a way to describe the steps you will be following to
solve any problem, usually written in pseudocode.
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Why?
● To simplify the solution of our problem.
● Create a roadmap/flow to carry out each
process.
•
Identify inputs and outputs.
•
Ease for programming.
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Example
● You go through series of steps while making a
transaction from an ATM
1. Insert card
2. Input pin and amount
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3. Take money
Flowchart
• Flowcharts are used to represent the flow
of an algorithm.
• The steps of the process is shown by
boxes and its flow is represented by
connecting arrows.
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Flowchart Symbols
● Different symbols have different meanings.
Some of the common symbols are shown below:
1.
The Oval
To represent Start or end of the algorithm.
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Flowchart Symbols
● Different symbols have different meanings.
Some of the common symbols are shown below:
2.
The Rectangle
One step is represented by a rectangle.
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Flowchart Symbols
● Different symbols have different meanings.
Some of the common symbols are shown below:
3.
The Diamond
Used while making some decision.
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Flowchart Symbols
● Different symbols have different meanings.
Some of the common symbols are shown below:
4.
The Arrow
To show the flow of the process
flow
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Flowchart Symbols
● Different symbols have different meanings.
Some of the common symbols are shown below:
5.
The Parallelogram
To represent the input and output
Input
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Output
Example
Make a flowchart that takes two
values from the user and print the
greater number.
Step 1: Start
Step 2: input number1
Step 3: input number2
Step 4: if number1 is greater than number2
Print “number1 is greater”
else
print “number2 is greater”
Step 5: Stop
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Program Structure in Python:
#Some programs discussed in last lecture
num1=5
num2=10
addition=num1+num2
variables
Operation
print(“My first python code”)
num=int(input("Enter number"))
square=num*2
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Values assigned
to variable
Program Structure in Python:
#Some programs discussed in last lecture
num1=5
num2=10
addition=num1+num2
print(“Hello World”)
num=int(input("Enter number"))
square=num*2
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Function to
display
content on
console
Program Structure in Python:
#Some programs discussed in last lecture
num1=5
num2=10
addition=num1+num2
print(“Hello Word”)
num=int(input("Enter number"))
square=num*2
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Function to
takeConverting
input
user
input into
from user
integer
comment
Activity
1. Write an algorithm of your admission process in UET
2. Make a flowchart for this process.
3. Write a code that takes five number as input
from user.
● Print the numbers
● Find mean and print it as well.
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Activity
1. Write an algorithm and code from the given flowchart
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Learning Objective
In this lecture, we learned about algorithm
designing, making flowcharts, meaning of
different shapes in flowcharts, and writing
programs in python.
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Conclusion
● Algorithms help us in solving problems by
creating different steps.
● Algorithms are not programming codes.
● Flowcharts are used to represent each step
of a process in the form of blocks.
● Every shape has different meaning in
flowcharts.
● In python,the program contains variables,
functions and operations.
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Take Home Tasks
1. Find out about different writing styles of
algorithms
2. Find out about different shapes of flowcharts and
their usage.
3. Maria has 4 bags while going to airport, she has
been told that she can take an average of 50kg.Tell
her to input the weights of each bag and calculate
the mean weight.
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